摘要 |
68432-58 A building panel of laminated construction having a flat, four-sided polygonal shaped hardboard sheet, to one surface of which is bonded a thin, flat, plastic sheet having weather resistant properties, and a rigid foam plastic layer having heat insulating properties bonded to the other surface of the hardboard sheet. The foam plastic layer has a tapered shape in cross section with the taper extending from a lower edge portion to a narrow upper edge portion. The hardboard and plastic sheets have an integral flanged lower edge portion in partial abutment with the lower edge portion of the foam plastic layer. A notch is formed in the lower edge portion of the foam plastic layer, adjacent the flanged lower edge portion, which notch is constructed and arranged to receive the upper edge portion of an adjacent lower building panel and thereby anchor the lower edge portion of the building panel and provide a seal at the joint. The method of fabrication includes the steps of forming the integral flanged lower edge portion by providing a V-shaped groove spaced from and parallel to the lower edge of the hardboard to a depth substantially at the surface of the plastic sheet without penetration of the latter and folding along the apex of the groove so as to bring the surfaces of the groove into abutment, the plastic sheet at the apex serving as a hinge. |